Monitoring Populations

1. Monitoring Populations 1. Populations of animals and plants may be monitored to provide essential data for a wide variety of purposes to include: a ) Management of species used for food or raw materials Information gained on increases or decreases in population numbers allows populations to be managed by • preventing over- exploitation of population through over-hunting or over- fishing. • allowing quotas to be determined • culling of individuals if population numbers are too high

2. b) Protection and conservation of endangered species Monitoring of populations shows which species are in danger of extinction and allows the conservation of endangered species by setting up and managing • wild life reserves • captive breeding programmes • seed banks c) The assessment of pollution levels by indicator species Indicator species are species whose presence or absence gives information on pollution levels in the environment.

3. The monitoring of indicator species is valuable as sources of pollution can be tracked and measures taken to reduce them • Lichens are able to accurately indicate levels of atmospheric pollution – See Lichen presentation • Freshwater invertebrates such as stonefly larvae, mayfly larvae, blood worms and rat tailed maggots can be used to measure levels of organic pollution – See Standard Grade Biosphere c) The control of pest species. Pest species are species which • reduce the species diversity of an ecosystem e.g. Rhododendrons or Japanese Knotweed • damage the commercial viability of other species used for food or raw materials e.g. fungi or moulds which grow in crops

4. multiply in unwanted environments e.g. any wild flower which dominates • a garden ( weeds ) Monitoring the spread of pest species allows effective control measures to be taken against them • What to do • Pupils should try the following past paper question • 2000 – Q12